Primary Ecomaths

Did you know that maths can help us protect our planet?

Maths can help us recycle old rubbish to make new things.

Maths can help us save energy in our homes and schools.

Maths can even help us grow our own food and much, much more.

Hiya, I'm Stef

and I'm going to show you how to get beautiful food like this

all the way from these fields onto your plate, using maths.

But this isn't any old maths,

this is the kind of maths that helps us to look to after the environment.

And I call it Ecomaths.

These fields belong to Wash Farm in Devon,

where they use maths to work out the most environmentally friendly way

to get food to our plates.

This is Ed and I want to find out what he's picking.

Hi, there, Ed, what are you up to?

Hi, there, Stef. I'm picking spring greens.

Look at that. That's absolutely beautiful.

What journey is this handful of greens going to make

from here until it gets onto my plate?

Well, once we've picked it in the field,

we'll take it back to the farm where it'll get stored,

probably, just over night.

After that, it'll get packed into a bag and into a box

and then, it gets delivered locally to our customers.

Can you take me to where this goes next? Yeah, certainly.

So, our food journey starts in the field.

The next stop is just a few minutes tractor ride to the farm itself,

where I meet James.

So, I've just come back from your fields.

What happens in here?

This is where we will weigh the product

when it arrives into our packhouse, then put it into a fridge

to store it, we then move it to our packing lines,

so we're putting it into bags or into a box,

before going onto our lorries.

Every stage in the journey uses energy.

This store is like a giant fridge that uses electricity.

Here is the packing line for the spring greens.

The spring greens are being put into bags,

each one weighs about 400g.

What else comes from the local fields?

Well, believe it or not, even in the middle of winter,

the farm grows salad leaves.

This polytunnel is like a massive tent

to protect the plants from the harsh winter weather.

This is called Claytonia.

It's really succulent. Mmm. And why'd do use this one?

We use this one because it counterbalances

some of the other more strong flavours.

So, a very mild flavour, isn't it?

so it can grow more leaves again.

There's maths everywhere you look.

This is Golden Mustard.

These are all planted by hand and they're planted 15cm apart.

And why does it need to be 15cm?

Why can't you just pack loads of them in?

It needs a certain amount of air and ventilation to help it grow well.

If you planted them much closer together,

you'd probably only get the same amount growing.

It's just, instead of having three large ones like we have here,

we'd have six very small ones. What else goes into the salad?

This is Rainbow Chard.

And this is dandelion.

Golden Streak Mustard.

And just break it all up.

These crates of salad leaves have just arrived at Wash Farm

to be mixed.

Rainbow Chard.

And then, Dan, if you want to grab the dandelion leaves.

To make the salad, they mix two crates of dandelion,

two crates of Mustard, four crates of Claytonia

and one of Rainbow Chard.

Can you tell the difference by looking at them?

You would if you tasted them. Delicious!

After mixing the salad, they weigh out the mixture

and pack it into bags, using this machine.

At this time of year, Wash Farm can't grow everything

that its customers want.

So, some things come from far away, like these lemons.

The next stage is to make up a big fruit and veg box.

Hi, Lena, can I give you a hand? Hello. Yeah, you can.

How do I do it? First thing, gloves. Ooh, attractive(!) Yeah.

And I will give you a job to do spring greens. OK.

Bag, you just, when you take, fold

and squeeze on this box which is very full this week.

So, it's 400 grams of spring greens? Spring greens, yes.

There are ten items in the box, most are local fruit and veg,

but some have come from far away. Can you guess which is which?

cos if one person goes a bit slowly, everyone else has to stop.

Some of the boxes get sent to other parts of the country on big trucks.

It's a bit of the journey that uses fuel,

so they try to make sure the trucks are packed as full as possible.

Next morning, the local delivery vans arrive

and the final stage of the journey begins.

First, each order's checked,

then the boxes are packed tightly into the van.

The vans go from home to home,

using the shortest possible route to save fuel.

It's taken just two days

from the time that David placed the order online

to the delivery on his doorstep.

All right. See you next week, thanks very much, bye. Bye.

I know somewhere where this challenge

of growing food as close as possible to where it's eaten

is taken even further.

Put both feet on it.

Arrrgh. Argh.

That's it. Right, OK.

At Ashley Primary School in Surrey, these children grow their own veg

in the school vegetable garden. And now, they're digging them up.

It's just a short walk from the garden to the kitchen.

We brought some leeks from the garden.

Lovely, thank you very much. I'll get those washed.

I want to find out about this brilliant school and its garden.

And what better place to start than the dining hall.

Max, where are the leeks that you picked from the garden?

In the curry, cos we grow loads of our own vegetables.

Do you grow a lot of the vegetables that you end up eating?

We grow quite a lot of the food we eat.

This tastes fantastic.

I think it tastes even better knowing that the vegetables

have just walked over the garden, over the football pitch, to here.

Those leeks taste so nice in the curry. Cool, isn't it?

Nothing is wasted.

The leftovers and waste from the kitchen feeds the chickens

and goes into the compost to feed the next crop of vegetables.

The children are measuring out the ground

and planting onions 20cm apart.

180.

Yes, I got the last one! 200. 200!

Why is it so important to space them perfectly, like this?

To obtain the maximum yield from the area that you're planting in

and also, just to make it easier to weed, basically.

So, how much do they save by using their own, very local food?

How much fruit and veg do you use each week?

We get through an average of four crates of fruit and veg a week.

How much do you think you'd save?

We could save at least two crates from the garden each week, I think.

How much energy are we saving, now we're getting it from the garden?

I'm not sure on how much energy,

but if we're going from four crates being transported in,

to two crates from our garden,

how much do you think that would be?

That would be about half. That's right

Good, that would be good. Yeah, that'd be very good. Very good.

They've just planted an orchard of apple trees.

It's a perfect rectangle, four-trees wide and six-trees long.

Can you count them for me?

ALL: 4!

Aaaand...

8!

And...

12!

And...

16!

And...

20!

And...

24!

Yeah!

Well, I've had a brilliant time here, learning all about growing

and planting your own, local varieties of fruit and veg

and using Ecomaths to help.

But, don't worry if you don't have a massive area like this,

you can still grow lots and lots of veg in a small tub

in your garden and you'll have delicious, local food

that won't cost the Earth and tastes absolutely fantastic.

Did you know that maths can help us protect our planet?

Maths can help us recycle old rubbish to make new things.

Maths can help us save energy in our homes and schools.

Maths can even help us grow our own food and much, much more.

Hiya, I'm Stefan, and I'm going to show you how to turn this...

into this.

Using maths.

But this isn't any old maths, oh, no,

this is what I call Ecomaths,

and it's a brilliant way to understand the world we live in

and to help make it a better place.

And the amazing thing about Ecomaths is it's everywhere around us,

it's even lurking in your rubbish bin.

How cool is this?

How many shapes can you see in this enormous mound of rubbish?

The first thing we need to do is sort this big mess out.

And that's what this place is for.

They sort it all into different shapes

that we find in the world around us.

So, here I am, actually, sorting some of this rubbish out.

I've got Richard with me,

he's going to explain how they use Ecomaths

to sort all this stuff. Richard, what is this amazing place?

This is a Materials Recycling Facility, a MRF.

We call it a Merf. A Merf! I love that. And what does a Merf do?

We take in all different types of packaging, newspapers, old bottles,

cans, things people don't want anymore,

split it all up and then re-use it.

We use the different machines to separate by the shape

of the material and the weight of the material.

So, the first thing that it comes to is a screen with rotating discs,

which allows paper to go over the top, cos it's thin and light

and cans and bottles to fall through,

because they're heavy and round.

So, here I am, right in the middle of this massive place,

and I'm going to find out how well it sorts my rubbish.

We'll start off with my big cylinder, the bottle.

Let's see how it goes.

Ah! Straight through!

Now, for something a bit smaller.

Another cylinder, my aluminium drinks can.

Let's see what happens.

Ha-ha!

Straight through, it didn't even touch the sides!

So, now, time for a very different shape, a piece of paper.

"Don't throw me away."

But this is very wide, but it's very, very thin.

Let's see what happens to it.

Ah!

I've been recycled!

Now, time for the big fella, the cardboard box.

The big cube, let's see where it goes.

Oooh, it's not sure. Spinning around!

Right up the top.

It's sorted all of my recycling perfectly.

Imagine I am a plastic bottle. I've been chucked in the recycling

and I'm there with all my mates, all the paper and the rubbish.

What's my journey?

First thing that will happen, is you'll go over the screen,

the sieve, and you'll fall through the holes in the sieve,

cos you're small and thin.

And then, you'll go along a conveyor belt,

where a robot will look at you and see what colour you are.

Depending what colour you are, it'll push you into a different bin

with a jet of air.

Then, you'll come into here and people will check

there's no paper with you and make sure you go into the plastic bin.

From there, you go into the giant baler,

which squeezes all the plastic bottles,

takes all the air outside, so they become thin

and then we can put them into a bale, about one metre by one metre,

and then, they easily fit onto vehicles.

Woo-hoo!

And here we are, the Merf has finished its work

and turned all of that rubbish into these.

And this is a beautiful bale of plastic.

It's taken these shapes, these big, wide shapes,

and squashed them really, really flat.

And it's made a brand new shape out of it.

This is a huge cuboid made out of bottles all squished together.

Over here, is another big bale, completely made of aluminium cans,

it's beautiful!

And this one is another bale, all made out of cardboard.

They're all the same shape and the same size,

but they're slightly different weights.

The metal and the plastic are heavier than the cardboard.

And now, all of this can go off to be made into brand new things.

So, the cardboard can be used to make brand new cardboard boxes.

The aluminium cans can go off to make aluminium cans.

And the plastic, I think, is the coolest one of all.

The plastic can be taken off to be made

into brand new plastic bottles,

but if you're really clever and really cool,

you can make it into one of these.

A recycled plastic chair. Look at that!

What would happen if we didn't recycle this stuff?

Where would it go?

This type of material would just go in your normal bin

with your food and other things and go in a hole in the ground.

But most types of paper, plastic, metal and glass,

which is what comes in here, can be recycled pretty well.

What's the most bizarre thing you've ever had come through here?

In one of our facilities, we once had a live boa constrictor snake.

It was this thick. Ha-ha! A live snake!

You really do need the gloves, then? Yeah, you need the gloves.

We can all do our own rubbish sorting,

like at this Eco-School in Peckham.

Ready, goooo!

What a mess!

What sort of bottles are really good to use?

Two-litre bottles like this. Two-litre bottles.

They're doing the same job as the machines did

at the recycling plant.

Sorting out plastic bottles into different shapes and sizes.

So, guys, are these ones any good? No. No? Why's that?

Cos they're too small. Too small, OK.

OK, that seems pretty good, let's put a few more up here.

Ooh, look, this is looking brilliant.

Right here.

Going that way round.

Nine.

Ten.

So, OK, has everyone got ten in their bag? Yes.

Exactly ten in their bag? Yeah.

Guys, are we ready to count? Yeah!

OK. One, two, three. Go!

ALL: Ten.

20.

30.

40.

50. 60.

70.

80.

90.

Brilliant! Well done, everybody!

But what are they going to use them for?

Let's take a look.

Have you got enough bottles here? Do you want another one?

There you go, there's one more.

By using Ecomaths

to sort out our rubbish into different shapes and sizes,

we can re-use things like water bottles

and make loads of useful stuff.

So, what are you up to here? We're planting sweet peas.

Oh, brilliant, can you show me how to do it?

First, you have to get a seed. Yeah.

And then, you put your finger down. Make a big hole. Yeah.

And then, you have to measure 15cm long

and then, you put your seed in and then, you cover it.

What do we do next? We put a brand new cloche onto it. Uh-huh.

And what's the cloche made of?

It's a recycled bottle that we collected and it's round.

That's fantastic.

So, you've stuck it over the top and the slugs can't get to it

and it'll keep the plant nice and cosy. Yeah. Brilliant.

Is that the coolest thing you can make out of recycling? Noooo!

So, what are you up to here? Putting bird feeders up.

And how've you made the bird feeder?

We cut a shape out of the bottle and then put the bird food in.

That looks absolutely brilliant. We can use it for different stuff.

Excellent, well done, I think this looks great.

Is this the coolest thing you can make out of recycling? Noooo!

So, what is the coolest thing you can make out of recycled bottles?

A greenhouse! Yeah!

A greenhouse made from 1,500 plastic bottles.

Now, that's brilliant.

Did you know that maths can help us protect our planet?

Maths can help us recycle old rubbish to make new things.

Maths can help us save energy in our homes and schools.

Maths can even help us grow our own food and much, much more.

Hiya, I'm Stef, and I'm going to show you

how you can help save energy and the planet, using maths.

But this isn't any old maths, this is what I call Ecomaths,

and it's a brilliant way to understand the world around us

and to help make it a better place.

Here at the Royal London Hospital, they look after lots of people

and help them to get better quickly.

In a place like this, you can discover lots of maths

and measurements going on all around you.

Have you ever had your temperature taken?

This girl has hers taken four times a day.

Before I find out about the maths,

I'm going to read a story to some of the children.

Once upon a time, there were three bears

and they lived in a house in the woods.

In the house, lived Daddy Bear, Mummy Bear and Baby Bear.

Daddy Bear made porridge, but it was too hot.

So, Mummy Bear, Daddy Bear and Baby Bear

went for a walk in the forest to let their porridge cool down,

when along came a little girl called...

Goldilocks.

Goldilocks, exactly.

Goldilocks went into the bear's house

and, on the table, were three bowls of...

Porridge. Porridge, exactly.

Goldilocks tried the first bowl of porridge,

but it was too cold. Eurgh!

So then, Goldilocks tried the second bowl of porridge.

Ooh! It was too hot!

Goldilocks tried the third bowl of porridge.

Oooh-ho-ho! It was just right.

Not too hot, not too cold, but just right.

So, Goldilocks gobbled it all up. Yum, yum.

So, Goldilocks had a problem.

Three bowls of porridge, but she didn't know which one to eat.

Which would be too hot? Which would be too cold?

Which would be just right?

The thing is, I'm lucky because I've got one of these.

It's a thermometer

and the thermometer will tell me the temperature of the porridge.

I've got one over on Goldilocks.

So, porridge number one is...

15 degrees. Eurgh! That's way too cold, it'd be disgusting.

One in the middle.

That is... Ah! ..70 degrees.

That would take your tongue off.

Way, way too hot.

Let's try the last one.

Ah-ha-ha!

That is 40 degrees,

exactly how I like it. I'm going to eat it.

We measure the temperature of porridge to see if it's just right

and good to eat.

We measure the temperature of people to check if they're well.

How about the room?

Jenny, why is it so important to control the temperature in the ward?

By keeping the temperature at a normal level,

it helps the patient to recover quicker.

The radiators are on a lot of the time

and there's no way to turn them down.

The only way to cool the room down

is to turn the air conditioning on or open the window.

The heat's on quite high all the time. Yeah.

And you're opening the window, to let the heat out. Yeah.

It's quite a strange thing to do, isn't it?

You're letting the energy nip out the window. Escape, yeah.

They're building a new hospital next door.

I wonder how they'll control the temperature.

This is Fiona.

Now, it just seems crazy to me that, in order to control the temperature

in the ward, you have to open the windows.

Isn't that a waste of energy? Absolutely.

It's a huge waste of energy.

And that's one of the reasons why we've built the new hospital,

because it's far more energy efficient.

They spend ?5 million on heating this hospital, every year,

so they need to save energy wherever they can.

So, how do you heat a building as huge as this hospital?

So, this is the main boiler house. Wow!

And we have six big boilers in here. So, they're heating the air

that's coming in from the outside and putting it into the hospital.

And then, before we send it out the other side of the building,

we don't just open the window and let it all go into the atmosphere.

We take the energy and the heat that we can

and we send it back through these pipes and back into the system,

so we don't have to heat it up again, so we don't waste any energy.

So, this is the control room. Yep.

Basically, there's a lot of thermometers around

and every room has a temperature thermometer

and then we measure it and monitor it here.

Can you change the temperature from the computer room?

Yes, you can go into any room

and you can turn the temperature up or down in any room.

So, you can control a room right on the other side of the hospital,

here, in this very room? Right from here.

So, why is it important that a room is not too hot, not too cold,

but just right? OK, so, it's really important

because, obviously, we need to make sure

that the children aren't too hot or too cold when they're in hospital

and, also, we need to make sure that we're not wasting any energy.

And turning down just one degree can make a huge, huge difference.

So, this is the new hospital.

This is where all the children will be moving into.

And you can feel the temperature.

The temperature in the old hospital... Was really hot.

..really hot. This is kind of perfect, isn't it? Yeah.

There's a few things that we've got in here,

these windows, don't open at all.

They're completely sealed, so you can't open them. Why's that?

So no energy can escape, so we can control the temperature really well

within the building.

Then, on the outside, here, we've got these solar deflectors.

They stop the sun coming in, during the summer,

and heating the building up. So, these deflect the sun.

Bounces off the building completely.

So the building stays really nice and cool.

And if you were a little bit too hot, a little bit too cold,

can you still control the temperature in here?

Yeah, you control it a little bit

and we can show you that over here, on the thermostat.

So, they can turn it up or down by one degree

if they're too hot or too cold in the room.

The rest of it is all controlled

by the main control panel downstairs? Yes. That's genius.

I've come to this Eco-School in Bristol

to meet some really cool kids. And the reason they're cool

is cos they're taking the temperature of this place

into their own hands

and, that way, they're going to save energy.

All you need to save energy

is something to measure the temperature

and a way of recording it. Oh, and some pupil power.

This is a temperature thermometer

and it tells you if we're wasting lots of energy.

And so, what does this one tell us?

It's 21. 21.

25.

So, what've we got here?

The temperature here is 19, which is very good for us.

That's much better, isn't it?

So, that's really good, isn't it?

19 is pretty nearly ideal temperature. Yeah. OK.

Wow. So, what's this room? The staff room.

The staff room. Are you guys allowed in the staff room?

No. Ha-ha.

Let's see what kind of temperature they have it here. 23.

23!

That's amazing. There's some real surprises,

but, unless you look at the thermometers, you would never know.

It's all very well collecting numbers,

but what do you do with them?

Well, that's where the maths kicks in.

Let's find out what's going on in here.

So, guys... So, Zane, can you show me what you're doing?

We're doing a bar chart. Uh-huh.

So, Lola, what can you tell me about the bar chart?

That it's telling us which classes save the most energy.

And what have you learnt?

That the class that hasn't been saving the most energy is Holly

and the one that saves the most is Beech.

The highest bar means when it's really, really hot.

And the lowest bar means it's really, really cold.

Cool.

These are some of the best bar charts I've ever seen.

These cool kids are making a huge chart in the hall.

They've used a pink ribbon to show the ideal temperature,

at 18 degrees.

You can see that most of the classes could save more energy

and only Beech class is really cool and wins the energy saving contest.

The brilliant thing about this eco-project

is that it makes everything so clear.

All of these temperatures are just a mess of wasted energy,

until you use maths to really understand it.

And then, you can get a big picture like this

and you can begin to make a difference.

Did you know that maths can help us protect our planet?

Maths can help us recycle old rubbish to make new things.

Maths can help us save energy in our homes and schools.

Maths can even help us grow our own food and much, much more.

Hiya, I'm Stef, and I've come here to one of the biggest greenhouses

in Britain to find out how they use maths to water the plants.

This is what they're growing in here.

Cucumbers. It's one of my favourite veg.

And why are they growing them in a greenhouse?

Well, it's freezing cold out there.

And there's two things that you need to grow cucumbers with,

warmth and a heck of a lot of water.

Now, this place is enormous,

but I need to find somebody who can tell me all about it.

Hi Judy, how you doing? Hello.

Tell me about this extraordinary place.

This is the biggest, most environmentally-friendly

cucumber greenhouse in the United Kingdom.

It's vast, isn't it? I think if you grew food on the moon,

you'd probably do it a bit like this, wouldn't you?

What do you need to grow cucumbers?

You need warmth, you need water

and, of course, you need some food as well.

I can't see anyone with a watering can,

how do you water the plants?

We have a big, computer-controlled system

that waters the plants for us.

A cucumber is mainly water. It's about 96% water.

To grow one, it takes about four litres of water.

The computer-controlled system puts this water and nutrient mix

through this dropper, and that dropper is water and nutrients.

Anything that the plant doesn't absorb,

we catch in these little trays at the side, here, and we recycle that.

About 30% of the water that we use everyday

is recycled from the previous day.

That is genius. Where does the water here come from?

We capture the water on the roof of the greenhouse

and we keep that in a reservoir outside.

And why do you collect rainwater, why not just turn a tap on?

Why do you need to collect it? Tap water's been treated.

Our plants, they just need untreated water. They just need the rain.

It's cheap, it's there, it seems crazy not to use it.

Yeah, it's free. It's free! We've got a really big roof,

so, instead of just letting the water fall off it into the ground,

we capture all that water and we use it to build strong, healthy plants.

More than a billion people on the planet have no access

to clean drinking water, yet, we take it for granted,

even using it to wash our cars and water our gardens.

So, rainwater could be an alternative.

You've got to have a roof to collect it and somewhere to store it.

And that's where the maths comes in.

Let's start with something we all know, a litre-bottle of water,

but a litre can come in lots of different shapes.

Take a look at this.

I'm going to pour my litre into a big cylinder,

goes into there.

I'm going to try putting it into a square container.

There we go. Again, same litre of water

and it's in a container that's 10cm by 10cm by 10cm.

It's exactly a litre. Now, take a look at this.

A litre of water can also be in the shape of a puddle.

Now, I've got a frame here that's exactly one metre

by one metre square.

And I've got four litres already poured into it.

I'm going to add one more litre of water

and, if I've got my maths right,

this should be 5mm high.

5mm, so I know that this is exactly five litres.

So, a litre of water comes in many shapes.

In the metre square frame, it's a puddle, 1mm deep.

So, five litres is a puddle 5mm deep.

Put another way, for every millimetre of rain that falls

on a square metre of roof, you get one litre of water.

I want to work out how much water I can get

from this whole, massive roof.

So, I need to work out the surface area in square metres

and then, multiply that by the rainfall in millimetres.

First of all, I've got to measure it. Give us a minute.

So, that was...

It's about thir...

Oh, got to do it again.

I found out that the area is an incredible 61,000 square metres.

Not by pacing it out, but by asking an expert.

This is Rob. So, Rob, how do you go about harvesting rainwater?

It sounds like a really odd idea.

It's a big word for a very simple thing.

Basically, we're collecting all the rain that lands on the roof

of this big greenhouse. How much water do you use in a year?

We use around about 70 million litres of water. Wow.

That's a lot of cucumber. That's a lot of cucumber,

but, again, that's over an area, of 61,000 square metres.

And how much of that water that you use

is rainwater that you've collected?

It depends how much rain we get each year,

but we would say, on average, around 35 million litres, so around half.

Nearly half of it, literally, just falls on your roof.

That is amazing, isn't it?

Conserving water is massively important

because, every time you turn on the tap,

the water that comes out has been purified,

it's been piped for miles around the country

and it's used a heck of a lot of energy in the process.

So, we shouldn't waste water

on things that don't need it to be pure.

Things like washing your car or flushing the loo or watering plants.

Now, this place is amazing.

But you don't need acres and acres of glass

and super hi-tech, computer-controlled kit

to harvest rainwater.

I'm going to meet some people who have a much simpler idea.

This is Peatmoor Primary School near Swindon,

where they have lots of roofs and lots of rain.

850mm per year.

Hi, guys. So, what are you up to here?

Well, we're doing a rain harvesting project. And how does that work?

When it rains, it falls onto the top of the shed,

it trickles into the gutter,

there's a tube down here to land into the watering butt.

So, how do you work out

how much water you're going to get from this roof?

First, we get the length times the width

and then, we times it by the average rainfall, that's 85cm a year.

While you measure how much water you're going to get,

can you show me where you use the water?

At the school, they have a massive eco-garden.

So it's a bit like an outdoor classroom?

While some of the children finish off the measuring,

I take a look around.

But it's huge.

How much water do you reckon you're going to need to water it?

Lots. Masses, aren't you?

So, can they collect enough rainwater from the shed roof

to water the garden?

How much can they harvest in a year?

Let's go find out how you're mates are doing.

How you getting on working out how much water there is?

Good, we just got the answer. It's almost 7,000 litres.

Wow. So, how did you work it out?

We've taken the width and the length and we've times it together.

1.91 metres and 4.28 metres.

We times that together to get 8.2metres squared.

That's the area. That's the area.

Then, we times that by the average rainfall, that is 850mm.

That got us to about 7,000 litres. Nearly 7,000 litres.

You can get a lot of water from one shed, can't you? Yeah.

That's not a big shed, it's a lot of water.

But, do you reckon it's enough water for the garden? No.

No, it's nowhere near enough water for the garden

for the whole year to grow all the vegetables.

So, what are we going to do if we need more water?

Well, we could always try a much bigger roof.

OK, so, we're going to do the whole thing. Put your arms up in the air.

The whole thing! OK, ready, guys? And go!

Wind up the tape measures.

OK, and back over here.

That is a nightmare, has anyone got a better idea? Yeah!

All right, show us.

Ah-ha! So, what is this?

It's the plan of the school.

Brilliant. We don't need to measure outside,

we can take it from here? Yeah.

Fantastic. OK. So, that's the roof that we were just trying to measure.

How do we measure it?

The scale is one to 100, so 1cm equals a metre.

16cm.

16cm equals how many metres? 16 metres.

So, the roof is 430 square metres?

430 times by 850.

So, what's the final figure? 365,500 litres.

365... Is that a big number? Yeah!

That's a whopper, isn't it?

What do you think you could do with that water?

Well, it could water the whole garden

and it can run the toilets for a whole year.

It could do the whole school, couldn't it?

You guys are brilliant, thank you so much.

The brilliant thing about rainwater harvesting

is that it doesn't need to be done on a massive scale.

When you do the maths, you realise

that even a small roof can get a huge amount of water.

Why don't you try it on a roof near you?

Did you know that maths can help us protect our planet?

Maths can help us recycle old rubbish to make new things.

Maths can help us save energy in our homes and schools.

Maths can even help us grow our own food and much, much more.

Hiya, I'm Stef,

and I'm going to show you how you can help save the world using maths.

I know that sounds a bit weird, but this is Ecomaths,

and it's a brilliant way of using maths in the real world

to help make it a better place.

Watch this. Taxi!

Hi, there. Station, please? Yeah.

I want to look at cars.

We all know that they use up precious energy,

they cause pollution and are bad for the environment,

but we like them because they're convenient and they're cosy,

and most importantly, we think that they're pretty fast.

But I want to know if that's really true,

so I'm timing how long it's going to take me

to get to the centre of Bristol in this taxi.

Going pretty fast actually!

Oh, we're here.

13 mins 57 secs.

Not bad.

I'm back where I started,

I'm going to make exactly the same trip again but in a different way.

There you go. Thank you. Hop on.

I'd never ridden a rickshaw, but here goes.

Off to the station again.

Looks like I'm pedalling and Ian's my passenger.

He knows about reducing car use and saving CO2 by going by bike.

This is the Bristol to Bath path.

This is the oldest cycle path in the country?

That's right.

It's looking good, isn't it? I though it'd be full of footholes.

Well they look after it really well and that way is Bath

and this way where we're going is Bristol.

Do that many people use it every year?

You'd be surprised.

This is one of the busiest in the country.

On a nice summer's day, 3,000 people will cycle down it just on that day.

but being in cars, then we'd have a huge traffic problem.

So it's relieving the roads in this whole area.

Just down there, I can see a little traffic jam, kinda think, ha ha!

Neeooow!

I suppose building cycle paths like this,

that comes with its own cost and problems, doesn't it?

Certainly, there are materials used there's time and energy

embedded in actually making these paths.

We've got to persuade people to make that change

from car use to walking and cycling

to be able to pay off the carbon embedded in the path.

Cycle paths are a great way to encourage people to cycle

instead of drive, but to build them we have to use machines

and materials that use energy and produce carbon dioxide.

Time to hop off the rickshaw and talk to Francis,

project manager of Bristol's latest cycleway.

So what's the carbon cost of building this cyclepath?

For this particular path, which is one kilometre long,

it's about 115,000 kilograms of CO2.

These workmen back here will be using carbon

in building the thing?

That's right and the specialised machinery they'd use

to build the path.

How do you work out how you save carbon? How do you do the maths?

For each person who converts from a car journey to a cycle journey,

we save 0.17 kg of CO2.

We calculate how many trips people make on a path like this per day.

So, we're estimating it'll be between 500 and 2,000 trips per day.

That's brilliant.

I never knew it was so fascinating that there are numbers

sitting in the cycle path.

I can't wait to have a go on it.

Take care! Time to do the maths.

We need to work out how much carbon we have to save

to pay back the carbon cost of building the new cycle path.

First of all, what's the difference between a bike and a car?

Well the difference of a kilometre by car

and a kilometre by bike, is a saving of 0.17 kg of CO2.

Brilliant.

OK and how many trips?

There's an average of about 500 trips per day.

500 a day? OK.

We should be able to work out how much carbon we save everyday

and how much is that then?

It's 500 times 0.17 which equals 85 kg of CO2.

OK, so over a year?

Well 85 kg of carbon per day

would equal 31,000 kg of C02 over a year.

Wow, OK.

At 31,000 kg of c02 per year, after four years,

they'll have saved over 115,000 kg of C02,

the original carbon cost of the cycle way.

After four years, what happens then?

Then you've broken even and then you're into carbon saving.

Almost at the station now, not really faster than a taxi,

with all the stopovers, but far healthier.

Yes, we're there! We're here!

Brilliant!

Thank you for driving me here.

That's a great pleasure. That was brilliant!

I'm not sure if that was actually any faster,

but it was brilliant, I've had a great time.

It makes you feel good about the day.

Brilliant, glad you enjoyed it. Thank you very much, take care.

Are people changing their ways and leaving their cars behind?

Until we do the math, we don't know!

Which is why I've come to Chester Park Primary School.

Ian has organised a free bikers breakfast this morning,

to encourage the pupils to cycle to school.

But has it worked?

I'm joining some pupils to collect the data.

Ethan, how'd you get to school?

I walked to school today. Thank you.

Tianna, how did you get to school? I drove today, Manny, so it's a car.

Thank you. Ben, how'd you get to school? Walked.

I cycled to school.

I walked. Drove. In a car. Walking. Thank you.

They collect the data sheets from every class in the school,

and then the maths kicks in.

5, 6, 7, 8, 9, 10, 11, 12, 13, 14.

Totals?

My grand total is 234.

Have you got 12 for car or van? Yes.

Guys, can you tell me what you're up to?

What we're doing is somebody asked us

how people come to school.

We will get the data, then we'll go and put it into a spreadsheet.

How have you worked out

the percentage of people that came by bike?

Divide that number, which is 36, by 239,

the number of people who are present in school today,

and then times it by 100 which would give us the percentage.

Scooter. 14 divided by 237.

Times that by 100 and you get your answer. 5.90.

So, scooter's pretty high! That's not bad.

Brilliant guys, OK, so what have you come up with?

I've done a bar chart showing how many people from each class,

how they came to school.

What can you see? Which class do think has done best?

I think it's probably 5C because they've got right to the top,

so that's 18, with walking and scooter.

Car and van, I would've thought would've been a bit lower.

Why do you think that is? Maybe cos of the temperature.

It's quite cold today, isn't it?

Maybe a few people more than usual came by car.

That's brilliant, well done.

Next, they use information from Bristol City Council

to compare today's total with the average for last year

in terms of carbon emissions.

We were trying to find out the change between last year's C02

emitted per pupil to this year's C02 per pupil.

The figure from last years 2010-11 C02 per pupil was 45.38 kg emitted.

Today's C02 per pupil was 42.2 kg, the difference was 3.18 kg.

A 7% decrease since last year.

So why do you think there's a 7% difference?

Because there's been a new year group come in and one leave.

Maybe more people walk or cycle to school in the year three group

than people drove to school in the year six group last year.

Today we had a Bike It Breakfast, lots more people will cycle

because they want to have a free breakfast.

Looks like Ian's Bikers Breakfast, may be working.

So, now for the fun stuff!

It's time to join Ian and the pupils for a bike ride.

In the end, it's safe, it's fast and it's fun to leave the car at home.

Let's go!

Did you know that maths can help us protect our planet?

Maths can help us recycle old rubbish to make new things,

Maths can help us save energy in our homes and schools,

maths can even help us grow our own food and much much more.

Hi, I'm Stef and I love my food but sometimes I've just had enough.

Now that waste ends up going to landfill

which is basically a huge hole in the ground.

What's the problem with that?

7.2 million tonnes, that's the problem.

That's how much food and drink we through away in the UK in a year.

I met up with Pamela from Wastewatch for a picnic lunch in the park.

How do we end up throwing away so much food in our homes?

There's two main reasons.

The first is that people perhaps buy too much,

or food has gone off before we've a chance to eat it.

Or stuff is... you've opened it and used it

but you haven't used it all by the time the use by or expiry date goes.

Second one, is where you've perhaps cooked too much food

or served too much food.

It's your plate scrapings or it's perhaps the leftover pasta or rice

which are big problems that end up going in the bin.

How much of the food produced actually ends up in our mouths

and how much gets chucked away?

To explain, I have a pie.

I'm going to turn this pie into a real life pie chart.

The whole pie represents all of the food that we could consume.

Here are the slices.

This first slice, around 7%, represents unavoidable food waste.

Things like banana skins and egg shells

that you have to throw away cos you can't eat them.

This next slice is about 10 %

and this represents avoidable food waste in our homes.

Food that's thrown away before it is cooked or after it's cooked.

Maybe you've bought too much food and it's gone mouldy,

you've taken too much on your plate

and you've had to scrape it into the bin.

This next piece is nearly as big, at 9%

and that's the waste from the supply chain.

That's 3.6 million tonnes.

Out of our whole pie, 26% of it is wasted.

That's more than a quarter. Why does it matter?

When food rots down, it produces methane

which is a really powerful greenhouse gas.

But as well as this, it is also a real waste of time,

of energy, of money, of resources, of water.

Avoidable food waste

is the equivalent of about 17 million tonnes of carbon dioxide

which is the same as if we took one of every five cars off the road.

Hang on a minute, have I got the ecomaths right?

Stopping food waste is the equivalent

to magicking one in five cars off the road.

Just imagine!

1, 2, 3, 4, gone!

1, 2, 3,

4,

gone!

1, 2, 3, 4, gone!

Now we know how much difference we could make

by reducing avoidable food waste in our homes.

The supply chain is everything that happens

before the food reaches us, and that's pretty wasteful too.

A big part of that is down to supermarkets.

I've come to this supermarket to find out

how food waste can be tackled using a little bit of thought,

a little bit of maths too.

This is Dan, who runs the fruit and veg.

In fruit and veg, we see three main ways that we tackle the waste issues.

Let's go with tomatoes.

We're heading over here.

What does Dan do if he finds a tomato that's not quite perfect?

Is it something you'd be happy taking home and eating?

Probably you'd be able to cook with it.

So, we head over this way.

We have a free box which customers can just help themselves.

We're not happy to charge them,

but we think it's worth taking home and doing something with it.

You pop it in the free box?

What we try to avoid is having things like that in the free box.

Much better home for this.

I don't think anyone's going to want to eat that. It looks a bit mouldy.

That's too far gone.

You'll find on here...

a big bag of compost.

So what happens to all of this? So, we've got a local producer

who grows a lot of salad leaves for us through the year.

They're two miles down the road and every time they deliver to us

they take these bags back with them.

One other things that we do

with vegetables that aren't quite fit to sell to the customers...

Nothing really wrong with these carrots,

they're just a bit dry, a bit sorry for themselves. But...

..what we have over here is the deli,

preparing fresh food for the public every day.

One giant pot of soup. So that's...

So that is heading that way.

It's a brilliant way to make use of something

that you've just got a few to many of.

If we're honest, to make money.

The public pay for nice soup. Brilliant. Now I'm hungry!

So, let's do the maths.

On average, they order 18 tonnes of fruit and veg per week.

About 97% is sold through the tills,

and 3% goes to the deli,

the free box, or to compost.

Is there a lot of number crunching involved?

To minimise waste, everything's got to be pretty accurate

and monitoring trends of how customers are buying.

The sunshine comes out, they buy strawberries. The sunshine goes in...

all of a sudden those strawberries are sitting there going nowhere.

So it's not just numbers, it's everything - the whole package.

By keeping the numbers really tight,

and judging what you'll sell,

you might get it wrong and sell out a little early,

but you're less likely to waste.

Remember, of the 18 tonnes of fruit and veg Dan orders a week,

around 3% is not sold.

That's 540 kilograms, or more than half a tonne of food,

that's not wasted and doesn't end up in landfill.

Good job, Dan!

I've found out masses about food waste so far,

but I know somewhere else where they are using eco maths

to help change our wasteful habits.

So here I am at Newton Ferrers School,

where they've got a team of food waste heroes

and they've been discovering some extraordinary things

about their school dinners.

The pupils are getting ready

to measure all the food waste and packaging this lunch time.

They've decided to compare school dinners and packed lunches.

Fantastic. So, I've got a sweet potato curry.

I can't believe there will be any food waste, it looks fantastic,

but we'll find out.

'The children who have packed lunches

'put their waste in the bins with the green labels.

'The school dinner waste goes into the grey bins.'

OK, so what do I do with this, then?

You take it over here to the...

OK, can you show me?

I feel really naughty doing that.

So, what's in there, quite a lot - a few flapjacks.

'Now it's time to do the weighing,

'and it's a messy business.

'All the school dinner waste has been poured into the green bucket.'

Lets keep the lid on that, that's disgusting.

6.28. 6.28. So what's in there? That's all the kitchen waste.

1.8 kilos, that's for the whole thing.

So that's all of the school dinners done,

now lets look at the packed lunch.

0.32. Brilliant.

This is all the data from this whole week

'Back in the classroom, they do the maths

'and calculate the total weight in each category.

'They need two pieces of information.

'Firstly, the weight of the empty boxes and bags.

'They did this before lunch. They also got the numbers of pupils

'having school dinners and packed lunches from the school office.

'Now they can work out the average per pupil.'

So, 5,920 divided by 71 school-dinner-eaters.

'The food waste from school dinners today

'was 83.4 grams per pupil,

'compared to...'

'..9.65 grams per pupil for packed lunches.'

So there's a big difference

between packed lunches and school dinners, isn't there?

'I've got a sneaking suspicion

'that some of the food waste from the packed lunches

'may be in bins at home.

'But for now,

'it looks like school dinners are more wasteful than packed lunches.'

So what do you do next? We need to make a graph.

'Finally, they prepare a pie chart,

'a bar chart, and a line graph

'to show changes in food waste

'for the four days of the food survey so far.'

It's great that this school is really trying to tackle

the amount of food waste that it creates.

But what's brilliant, is that they're using maths

to make sure that their campaign is based on real numbers.

Now, they're going to keep an eye on it over the next couple of months.

Will it be successful?

Well, only time and eco maths will tell.

Subtitles by Red Bee Media Ltd